Clinical pattern of ocular toxoplasmosis treated in a referral centre in Serbia

Purpose To analyze the clinical pattern of ocular toxoplasmosis (OT) in a referral centre in Serbia. Patients and methods The medical records of consecutive patients admitted for OT to the single referral centre for uveitis in Serbia between 2006 and 2010 were retrospectively analyzed. OT was diagnosed on the basis of typical fundus lesions and positive serology for Toxoplasma. Results In a total of 457 uveitis patients, OT was the third leading cause, with 59 patients (12.9%). Most OT cases (73%) were monocular. An active primary retinal lesion was observed in 36% and recurrent OT in 64% patients. Localization of lesions was central/paracentral (44%), juxtapapillar (27%), peripheral (19%), and multifocal (10%). Other ocular manifestations of inflammation included vitritis (44%), anterior uveitis (19%), and retinal vasculitis (10%). Complications included choroidal neovascularization in two and exudative retinal detachment with cataract, glaucoma, and cystoid macular oedema in one patient each. The detection of Toxoplasma-specific IgM antibodies in a single patient indicates a low rate of OT concomitant with acute infection. After treatment, the mean best-corrected visual acuity (BCVA) increased significantly. However, 14 (24%) patients ended up legally blind in the affected eye, of which 2 (3%) with bilateral blindness, all with a very poor BCVA (0.047 +/- 0.055) at presentation. Visual impairment and treatment outcome were both associated with central localization of lesions (P lt 0.0001 and P = 0.006, respectively). Conclusion OT is a significant cause of posterior uveitis in Serbia. Patients should be aware of the recurring nature of OT and react immediately if symptoms occur. Eye (2012) 26, 723-728; doi: 10.1038/eye.2012.20; published online 24 February 201

Molecular markers of susceptibility to ocular toxoplasmosis, host and guest behaving badly

Adriana Lima Vallochi1, Anna Carla Goldberg2, Angela Falcai3, Rajendranath Ramasawmy4, Jorge Kalil4, Cláudio Silveira5, Rubens Belfort Jr5, Luiz Vicente Rizzo31Oswaldo Cruz Institution (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, RJ, Brazil; 2NUCEL – Cellular and Molecular Therapy Center, University of São Paulo, São Paulo, SP, Brazil; 3Department of Immunology, Biomedical Science Institute, University of São Paulo, São Paulo, SP, Brazil; 4Laboratory of Immunology, Heart Institute, University of São Paulo Medical School, São Paulo, SP, Brazil; 5Department of Ophthalmology, Federal University of São Paulo, São Paulo, SP, BrazilAbstract: Infection with Toxoplasma gondii results in retinochoroiditis in 6% to 20% of immunocompetent individuals. The outcome of infection is the result of a set of interactions involving host genetic background, environmental, and social factors, and the genetic background of the parasite, all of which can be further modified by additional infections or even reinfection. Genes that encode several components of the immune system exhibit polymorphisms in their regulatory and coding regions that affect level and type of expression in response to stimuli, directing the immune response into different pathways. These variant alleles have been associated with susceptibility to immune-mediated diseases and with severity of pathology. We have investigated polymorphisms in several of these genes, identified as candidates for progression to retinochoroiditis caused by toxoplasmosis, namely chemokine (C-C motif) receptor 5 (CCR5), toll-like receptor-2 (TLR2), and TLR4. Furthermore, because interleukin-12 (IL-12) has been shown to be fundamental both in mice and in man to control a protective response against T. gondii, molecules that have a key function in IL-12 production will be emphasized in this review, in addition to discussing the importance of the genetic background of the parasite in the establishment of ocular disease.Keywords: ocular toxoplasmosis, IL-12, TLR, CCR5, immunit

High prevalence of unusual genotypes of Toxoplasma gondii infection in pork meat samples from Erechim, Southern Brazil

Toxoplasmosis is the most common cause of infectious uveitis in Brazil, with a higher frequency in the South of the country. We have collected samples from porcine tongue and diaphragm obtained in both large and small abattoirs and used molecular biological technique to determine the prevalence of infection and RFLP analysis to type the parasites. Seventeen out of 50 (34%) samples from the diaphragm and 33 out of 50 (66%) samples from the tongue demonstrated a positive PCR reaction for T. gondii and restriction analysis of four of the positive samples revealed that all had a type I genotype at SAG2. However, when other unlinked loci were analyzed, these strains had a type III genotype at markers BTUB, SAG3, and GRA6. One of the strains (8T) had a type II allele at SAG3, indicating it has a combination of alleles normally seen in the clonal lineages. Our sampling indicates a high prevalence of infection and suggests that unusual genotypes of T. gondii are found in Brazil even among domesticated pigs.<br>Toxoplasmose é a causa mais comum de uveíte infecciosa no Brasil, com maior freqüência no sul do país. Coletamos amostras de diafragma e língua de porcos em pequenos e grandes abatedouros e utilizamos biologia molecular para determinar a taxa de infecção e ''DNA genotyping'' para tipar os parasitas. Dezessete das 50 amostras de diafragma (34%) e 33 das 50 amostras de língua (66%) foram positivas na reação de PCR para T. gondii. A análise restritiva e o sequenciamento do DNA em quatro amostras revelaram que todas apresentam genótipo tipo I no SAG2. No entanto, quando outros loci não ligados foram analisados, estas mesmas amostras se mostraram como tipo III nos marcadores BTUB, SAG3 e GRA6. Uma das amostras (8T) mostrava-se como tipo II no SAG3, indicando um perfil misto. Estas amostras demonstraram não só uma alta taxa de infecção, mas também genótipos incomuns que não foram observados com freqüência em estudos prévios. Nosso trabalho sugere que genótipos incomuns de T. gondii podem ser encontrados no Brasil, até mesmo em porcos domesticados